The natural compound from Garcinia bracteata mainly induces GSDME-mediated pyroptosis in esophageal cancer cells

Diallyl trisulfide induces pyroptosis and impairs lung CSC-like properties by activating the ROS/Caspase 1 signaling pathway

Lung cancer stem cells (CSCs) drive continuous cancer growth and metastatic dissemination; thus, there is an urgent requirement to acquire effective therapeutic strategies for targeting lung CSCs. Diallyl trisulfide (DATS), a garlic organosulfide, possesses suppressive potential in lung cancer; however, its underlying mechanism is still unclear. In this study, we identified DATS as a pyroptosis inducer in lung cancer cells. DATS-treated A549 and H460 cells exhibited pyroptotic cell death, with characteristic large bubbles appearing on their plasma membrane and LDH release. DATS induced cell death, arrested the cell cycle at the G2/M phase, and inhibited colony formation in lung cancer cells. Meanwhile, we found that DATS significantly suppressed the malignant features by impairing lung CSC-like properties, including sphere formation ability, CD133 positive cell number, and lung CSCs marker expression. Mechanistically, DATS induced cell pyroptosis via increasing the expression of NLRP3, ASC, Pro Caspase 1, Cleaved Caspase 1, GSDMD, GSDMD-N, and IL-1β. The verification experiments showed that the effects of DATS on pyroptosis and lung CSC-like properties were weakened after Caspase 1 inhibitor VX-765 treatment, indicating that DATS activated NLRP3 inflammasome-mediated pyroptosis by targeting Caspase 1 in lung cancer cells. Moreover, DATS increased ROS overproduction and mitochondrial dysfunction, which contributed to DATS-induced pyroptosis of lung cancer cells. NAC treatment reversed the effects of DATS on pyroptosis and CSC-like properties. In vivo experiment further confirmed that DATS restrained tumor growth. Together, our results suggest that DATS promotes pyroptosis and impairs lung CSC-like properties by activating ROS/Caspase 1 signaling pathway, thereby retarding lung cancer progression.

Therapeutic strategies of targeting non-apoptotic regulated cell death (RCD) with small-molecule compounds in cancer

Regulated cell death (RCD) is a controlled form of cell death orchestrated by one or more cascading signaling pathways, making it amenable to pharmacological intervention. RCD subroutines can be categorized as apoptotic or non-apoptotic and play essential roles in maintaining homeostasis, facilitating development, and modulating immunity. Accumulating evidence has recently revealed that RCD evasion is frequently the primary cause of tumor survival. Several non-apoptotic RCD subroutines have garnered attention as promising cancer therapies due to their ability to induce tumor regression and prevent relapse, comparable to apoptosis. Moreover, they offer potential solutions for overcoming the acquired resistance of tumors toward apoptotic drugs. With an increasing understanding of the underlying mechanisms governing these non-apoptotic RCD subroutines, a growing number of small-molecule compounds targeting single or multiple pathways have been discovered, providing novel strategies for current cancer therapy. In this review, we comprehensively summarized the current regulatory mechanisms of the emerging non-apoptotic RCD subroutines, mainly including autophagy-dependent cell death, ferroptosis, cuproptosis, disulfidptosis, necroptosis, pyroptosis, alkaliptosis, oxeiptosis, parthanatos, mitochondrial permeability transition (MPT)-driven necrosis, entotic cell death, NETotic cell death, lysosome-dependent cell death, and immunogenic cell death (ICD). Furthermore, we focused on discussing the pharmacological regulatory mechanisms of related small-molecule compounds. In brief, these insightful findings may provide valuable guidance for investigating individual or collaborative targeting approaches towards different RCD subroutines, ultimately driving the discovery of novel small-molecule compounds that target RCD and significantly enhance future cancer therapeutics.

Insight into the structure, function and the tumor suppression effect of gasdermin E

Gasdermin E (GSDME), which is also known as DFNA5, was first identified as a deafness-related gene that is expressed in cochlear hair cells, and mutation of this gene causes autosomal dominant neurogenic hearing loss. Later studies revealed that GSDME is mostly expressed in the kidney, placenta, muscle and brain cells, but it is expressed at low levels in tumor cells. The GSDME gene encodes the GSDME protein, which is a member of the gasdermin (GSDM) family and has been shown to participate in the induction of apoptosis and pyroptosis. The current literature suggests that Caspase-3 and Granzyme B (Gzm B) can cleave GSDME to generate the active N-terminal fragment (GSDME-NT), which integrates with the cell membrane and forms pores in this membrane to induce pyroptosis. Furthermore, GSDME also forms pores in mitochondrial membranes to release apoptosis factors, such as cytochrome c (Cyt c) and high-temperature requirement protein A2 (HtrA2/Omi), and subsequently activates the intrinsic apoptosis pathway. In recent years, GSDME has been shown to exert tumor-suppressive effects, suggesting that it has potential therapeutic effects on tumors. In this review, we introduce the structure and function of GSDME and the mechanism by which it induces cell death, and we discuss its tumor suppressive effect.

Neobractatin induces pyroptosis of esophageal cancer cells by TOM20/BAX signaling pathway

BACKGROUND

Emerging evidence suggests that pyroptosis, a form of programmed cell death, has been implicated in cancer progression. The involvement of specific proteins in pyroptosis is an area of growing interest. TOM20, an outer mitochondrial membrane protein, has recently garnered attention for its potential role in pyroptosis. Our previous study found that NBT could induce pyroptosis by ROS/JNK pathway in esophageal cancer cells.

PURPOSE

This study aims to investigate whether NBT induces pyroptosis and verify whether such effects are involved in up-regulation of TOM20 in esophageal cancer cells.

METHODS

The University of ALabama at Birmingham CANcer data analysis Portal (UALCAN) was used to analyze the clinical significance of GSDME in esophageal cancer. MTT assay, morphological observation and Western blot were performed to verify the roles of TOM20 and BAX in NBT-induced pyroptosis after CRISPR-Cas9-mediated knockout. Immunofluorescence was used to determine the subcellular locations of BAX and cytochrome c. MitoSOX Red was employed to assess the mitochondrial reactive oxygen species (ROS) level. KYSE450 and TOM20 knockout KYSE450-/- xenograft models were established to elucidate the mechanisms involved in NBT-induced cell death.

RESULTS

In this study, NBT effectively upregulated the expression of TOM20 and facilitated the translocation of BAX to mitochondria, which promoted the release of cytochrome c from mitochondria to the cytoplasm, leading to the activation of caspase-9 and caspase-3, and finally induced pyroptosis. Knocking out TOM20 by CRISPR-Cas9 significantly inhibited the expression of BAX and the downstream BAX/caspase-3/GSDME pathway, which attenuated NBT-induced pyroptosis. The elevated mitochondrial ROS level was observed after NBT treatment. Remarkably, the inhibition of ROS by N-acetylcysteine (NAC) effectively suppressed the activation of TOM20/BAX pathway. Moreover, in vivo experiments demonstrated that NBT exhibited potent antitumor effects in both KYSE450 and TOM20 knockout KYSE450-/- xenograft models. Notably, the attenuated antitumor effects and reduced cleavage of GSDME were observed in the TOM20 knockout model.

CONCLUSION

These findings reveal that NBT induces pyroptosis through ROS/TOM20/BAX/GSDME pathway, which highlight the therapeutic potential of targeting TOM20 and GSDME, providing promising prospects for the development of innovative and effective treatment approaches for esophageal cancer.

Design, synthesis, and biological evaluation of gambogenic acid derivatives: Unraveling their anti-cancer effects by inducing pyroptosis

Gambogenic acid (GNA), a caged xanthone derived from Garcinia hanburyi, exhibits a wide range of anti-cancer properties. The caged skeleton of GNA serves as the fundamental pharmacophore responsible for its antitumor effects. However, limited exploration has focused on the structural modifications of GNA. This study endeavors to diversify the structure of GNA and enhance its anti-cancer efficacy. Sulfoximines, recognized as pivotal motifs in medicinal chemistry due to their outstanding properties, have featured in several anti-cancer drugs undergoing clinical trials. Accordingly, a series of 33 GNA derivatives combined with sulfoximines were synthesized and evaluated for their anti-cancer effects against MIAPaCa2, MDA-MB-231, and A549 cells in vitro. The activity screening led to the identification of compound 12k, which exhibited the most potent anti-cancer effect. Mechanistic studies revealed that 12k primarily induced pyroptosis in MIAPaCa2 and MDA-MB-231 cells by activating the caspase-3/gasdermin E (GSDME) pathway. These findings suggested that 12k is a promising drug candidate in cancer therapy and highlighted the potential of sulfoximines as a valuable functional group in drug discovery.

Engineering materials for pyroptosis induction in cancer treatment

Cancer remains a significant global health concern, necessitating the development of innovative therapeutic strategies. This research paper aims to investigate the role of pyroptosis induction in cancer treatment. Pyroptosis, a form of programmed cell death characterized by the release of pro-inflammatory cytokines and the formation of plasma membrane pores, has gained significant attention as a potential target for cancer therapy. The objective of this study is to provide a comprehensive overview of the current understanding of pyroptosis and its role in cancer treatment. The paper discusses the concept of pyroptosis and its relationship with other forms of cell death, such as apoptosis and necroptosis. It explores the role of pyroptosis in immune activation and its potential for combination therapy. The study also reviews the use of natural, biological, chemical, and multifunctional composite materials for pyroptosis induction in cancer cells. The molecular mechanisms underlying pyroptosis induction by these materials are discussed, along with their advantages and challenges in cancer treatment. The findings of this study highlight the potential of pyroptosis induction as a novel therapeutic strategy in cancer treatment and provide insights into the different materials and mechanisms involved in pyroptosis induction.

New prospects of cancer therapy based on pyroptosis and pyroptosis inducers

Pyroptosis is a gasdermin-mediated programmed cell death (PCD) pathway. It differs from apoptosis because of the secretion of inflammatory molecules. Pyroptosis is closely associated with various malignant tumors. Recent studies have demonstrated that pyroptosis can either inhibit or promote the development of malignant tumors, depending on the cell type (immune or cancer cells) and duration and severity of the process. This review summarizes the molecular mechanisms of pyroptosis, its relationship with malignancies, and focuses on current pyroptosis inducers and their significance in cancer treatment. The molecules involved in the pyroptosis signaling pathway could serve as therapeutic targets for the development of novel drugs for cancer therapy. In addition, we analyzed the potential of combining pyroptosis with conventional anticancer techniques as a promising strategy for cancer treatment.

Pyroptotic cell death: an emerging therapeutic opportunity for radiotherapy

Pyroptotic cell death, an inflammatory form of programmed cell death (PCD), is emerging as a potential therapeutic opportunity for radiotherapy (RT). RT is commonly used for cancer treatment, but its effectiveness can be limited by tumor resistance and adverse effects on healthy tissues. Pyroptosis, characterized by cell swelling, membrane rupture, and release of pro-inflammatory cytokines, has been shown to enhance the immune response against cancer cells. By inducing pyroptotic cell death in tumor cells, RT has the potential to enhance treatment outcomes by stimulating anti-tumor immune responses and improving the overall efficacy of RT. Furthermore, the release of danger signals from pyroptotic cells can promote the recruitment and activation of immune cells, leading to a systemic immune response that may target distant metastases. Although further research is needed to fully understand the mechanisms and optimize the use of pyroptotic cell death in RT, it holds promise as a novel therapeutic strategy for improving cancer treatment outcomes. This review aims to synthesize recent research on the regulatory mechanisms underlying radiation-induced pyroptosis and to elucidate the potential significance of this process in RT. The insights gained from this analysis may inform strategies to enhance the efficacy of RT for tumors.

Neuronal pyroptosis mediated by STAT3 in early brain injury after subarachnoid hemorrhage

Neuroinflammation induced by early brain injury (EBI) seriously affects the prognosis of patients after subarachnoid hemorrhage (SAH). Pyroptosis can aggravate inflammatory injury by promoting the secretion of inflammatory cytokines. Meanwhile, STAT3 plays a critical role in the inflammatory response of EBI after SAH. However, whether it plays a pyroptotic role in SAH is mainly unknown. This study aimed to explore the mechanism of STAT3 in pyroptosis in EBI after SAH. C57BL/6J mice were used to establish the SAH model. Brain tissues were collected at different time points for q-RT-PCR and western blot to detect the expression level of STAT3. After intracerebroventricular injection of STAT3 inhibitor S3I-201, they were divided into sham, SAH, SAH + Vehicle, and SAH + S3I-201. Then, the SAH grade, cerebral edema content, blood-brain barrier (BBB) damage, and neurological scores of mice in each group were detected. qRT-PCR and western blot were used to detect related genes and proteins, and enzyme-linked immunosorbent assay (ELISA) was used to detect the expression levels of IL-18 and IL-1β. Immunofluorescence staining was used to observe the expression level of proteins. At the same time, S3I-201 was added to the primary neuron cells of the culture medium containing OxyHb to simulate the in vitro experiment, and the relevant indicators consistent with the in vivo experiment were detected. The expression of STAT3 was upregulated after SAH. Inhibition of STAT3 with S3I-201 attenuated neurological deficits, cerebral edema, and BBB damage after SAH. In addition, S3I-201 can also reduce the expression of pyroptosis-related inflammasomes such as GSDMD, NLRP3, Caspase 1, and AIM2 after SAH and the neurological damage caused by IL-18 and IL-1β. Further studies have shown that STAT3 regulates pyroptosis by promoting the nuclear translocation of NF-κB p65. Our finding demonstrated that STAT3 regulates neuronal pyroptosis in EBI after SAH. Inhibition of STAT3 may be a potential target to attenuate the damage that triggers neuroinflammation after SAH.

Cytotoxic xanthones from Garcinia pedunculata fruits

Eight previously undescribed and seven known xanthones were isolated from the fruits of Garcinia pedunculata Roxb. The structures were identified by a variety of spectroscopic methods as well as by comparison with the literature. The isolates showed appreciable cytotoxicity against three human tumor cell lines (HepG2, A549, and MCF-7). Pedunculaxanthone G exhibited inhibitory activities with IC50 values of 12.41, 16.51, and 15.45 μM against the cancer cell lines and induced cell apoptosis in HepG2 cells.

Pyroptosis in glioma: Current management and future application

Glioma, the predominant form of central nervous system (CNS) malignancies, presents a significant challenge due to its high prevalence and low 5-year survival rate. The efficacy of current treatment methods is limited by the presence of the blood-brain barrier, the immunosuppressive microenvironment, and other factors. Immunotherapy has emerged as a promising approach, as it can overcome the blood-brain barrier. A tumor's immune privilege, which is induced by an immunosuppressive environment, constricts immunotherapy's clinical impact in glioma. Pyroptosis, a programmed cell death mechanism facilitated by gasdermins, plays a significant role in the management of glioma. Its ability to initiate and regulate tumor occurrence, progression, and metastasis is well-established. However, it is crucial to note that uncontrolled or excessive cell death can result in tissue damage, acute inflammation, and cytokine release syndrome, thereby potentially promoting tumor advancement or recurrence. This paper aims to elucidate the molecular pathways involved in pyroptosis and subsequently discuss its induction in cancer therapy. In addition, the current treatment methods of glioma and the use of pyroptosis in these treatments are introduced. It is hoped to provide more ideas for the treatment of glioma.

The multifaceted roles of GSDME-mediated pyroptosis in cancer: therapeutic strategies and persisting obstacles

Pyroptosis is a novel regulated cell death (RCD) mode associated with inflammation and innate immunity. Gasdermin E (GSDME), a crucial component of the gasdermin (GSDM) family proteins, has the ability to convert caspase-3-mediated apoptosis to pyroptosis of cancer cells and activate anti-tumor immunity. Accumulating evidence indicates that GSDME methylation holds tremendous potential as a biomarker for early detection, diagnosis, prognosis, and treatment of tumors. In fact, GSDME-mediated pyroptosis performs a dual role in anti-tumor therapy. On the one side, pyroptotic cell death in tumors caused by GSDME contributes to inflammatory cytokines release, which transform the tumor immune microenvironment (TIME) from a 'cold' to a 'hot' state and significantly improve anti-tumor immunotherapy. However, due to GSDME is expressed in nearly all body tissues and immune cells, it can exacerbate chemotherapy toxicity and partially block immune response. How to achieve a balance between the two sides is a crucial research topic. Meanwhile, the potential functions of GSDME-mediated pyroptosis in anti-programmed cell death protein 1 (PD-1) therapy, antibody-drug conjugates (ADCs) therapy, and chimeric antigen receptor T cells (CAR-T cells) therapy have not yet been fully understood, and how to improve clinical outcomes persists obscure. In this review, we systematically summarize the latest research regarding the molecular mechanisms of pyroptosis and discuss the role of GSDME-mediated pyroptosis in anti-tumor immunity and its potential applications in cancer treatment.

Irradiation Induces Gasdermin E-Triggered Tumor Immunity to Inhibit Esophageal Carcinoma Cell Survival

Gasdermin E (GSDME), an executor of pyroptosis, can be activated by caspase-3 and has been recognized as a tumor suppressor in various human cancers. In addition, caspase-3/GSDME signal-induced pyroptosis is a form of immunogenic cell death (ICD). In this study, we aimed to understand the association between radiotherapy and caspase-3/GSDME signal-related ICD in esophageal carcinoma (EC) cells. The expression of caspase-3 and GSDME in two EC cell lines, ECA-109 and KYSE-150, was silenced or overexpressed by transfection with specific siRNAs or overexpression vectors. Cells were subjected to 0-8 Gy irradiation, and cell death was evaluated by CCK-8 assay, annexin V-FITC staining, lactate dehydrogenase (LDH) detection kit, Western blotting, and immunofluorescence. Irradiation in both EC cell lines promoted dose-dependent viability loss and apoptosis. More specifically, 8 Gy X-ray increased the apoptosis rate from 4.1 to 12.8% in ECA-109 cells and from 4.6 to 21.1% in KYSE-150 cells. In irradiated EC cells, the levels of LDH release and caspase-3/GSDME cleavage were increased. Caspase-3 silencing inhibited irradiation-induced GSDME cleavage and EC cell death. Furthermore, we identified the death of EC cells suppressed by caspase-3 siRNA, and the levels of CRT, HMGB1, HSP70, and HSP90 were also markedly downregulated by caspase-3 siRNA. Similarly, GSDME silencing diminished irradiation-induced EC cell death and the levels of ICD markers. Overexpression of caspase-3 and GSDME accelerated irradiation-induced ICD. In summary, irradiation in EC cells induces GSDME-mediated pyroptosis and activates ICD to inhibit esophageal carcinoma cell survival.

Integrated analysis of diagnostic, prognostic value and potential drug treatment of GSDME in head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSC) poses a global health challenge. Effective biomarkers for early detection are necessary to improve the survival rate of HNSC patient. The purpose of this study was using integrated bioinformatic analysis to investigate the potential biological roles of GSDME in HNSC.

METHODS

The Gene Expression Omnibus (GEO) and Cancer Gnome Atlas (TCGA) databases were used to analyze the expression of GSDME in different cancer types. The correlation between GSDME expression and immune cell infiltration or immune checkpoint genes was examined by Spearman correlation analysis. DNA methylation analysis of the GSDME gene was conducted using the MethSurv database. Kaplan-Meier (K-M) survival curves, diagnostic receiver operating characteristic (ROC) curves, nomogram model, and Cox regression analysis were chosen to evaluate the diagnostic and prognostic predictive value of GSDME. Connectivity Map (Cmap) online platform, Protein Data Bank (PDB) database and Chem3D, AutoDock Tool and PyMol software were used to predict and visualize potential molecular drugs aimed for GSDME.

RESULTS

GSDME expression level in HNSC was significantly higher than in the controls (p < 0.001). Differentially expressed genes (DEGs) correlation with GSDME were enriched in the GO pathways, such as protein activation cascade, complement activation and classical pathway (p < 0.05). According to GSEA, GSDME-associated differentially expressed genes were significantly enriched in KRAS signaling pathway and cytokine signaling molecule (p < 0.05). There is a significant relation between GSDME expression and immune cell infiltration in HNSC tissues, as well as immune checkpoint genes expression (p < 0.001). DNA methylation status of cg17790129 CpG islands of GSDME gene is correlated with HNSC prognosis (p < 0.05). Based on Cox regression analysis of HNSC patients, GSDME as a potential risk gene has high correlation with overall survival (OS) and disease specific survival (DSS) (p < 0.05). In a ROC curve analysis, HNSC tissues were differentiated from adjacent peritumoral tissues based on GSDME expression levels (AUC = 0.928). Totally six potential drugs targeted for GSDME were screened and the molecular docking tests between GSDME protein and candidate drugs were conducted.

CONCLUSIONS

GSDME is a promising therapeutic target as well as a potential clinical biomarker in HNSC patients.

The pyroptotic role of Caspase-3/GSDME signalling pathway among various cancer: A Review

Cytotoxic drugs have long been recognised to kill cancer cells through apoptosis. According to a current study, pyroptosis inhibits cell proliferation and shrinks tumors. Pyroptosis and apoptosis are caspase-dependent programmed cell death (PCD) processes. Inflammasomes activate caspase-1 and latent cytokines, including IL-1β and IL-18, to cleave gasdermin E (GSDME) and induce pyroptosis. Gasdermin proteins activate caspase-3 to induce pyroptosis, which is associated with tumour genesis, development, and therapy response. These proteins may serve as therapeutic biomarkers for cancer detection, and their antagonists may be a new target. Caspase-3, a crucial protein in both pyroptosis and apoptosis, governs tumour cytotoxicity when activated, and GSDME expression modulates this. Once active caspase-3 cleaves GSDME, its N-terminal domain punches holes in the cell membrane, causing it to expand, burst, and die. To understand the cellular and molecular mechanisms of PCD mediated by caspase-3 and GSDME, we focused on pyroptosis. Hence, caspase-3 and GSDME may be promising targets for cancer treatment.

Alantolactone induces concurrent apoptosis and GSDME-dependent pyroptosis of anaplastic thyroid cancer through ROS mitochondria-dependent caspase pathway

BACKGROUND

Anaplastic thyroid cancer (ATC) is one of the fatal cancers and has not effective treatments. Alantolactone (ATL), a terpenoid extracted from traditional Chinese medicinal herb Inula helenium L., confers significant anti-inflammatory, antibacterial and antitumor activity. However, the activity and mechanisms of ATL in ATC remain unclear.

PURPOSE

To investigate the potential anti-ATC effects in vitro and in vivo and the mechanisms involved.

METHODS

The anti-proliferative activity of Alantolactone (ATL) against ATC cells was analyzed through CCK-8 and colony formation assays. Flow cytometry assay was performed to assess the cell cycle, cell apoptosis, ROS, and mitochondrial membrane potential (ΔΨm), whereas the cellular localization of cytochrome c and calreticulin were determined using cellular immunofluorescence assays. The lactate dehydrogenase (LDH) enzyme activity in the cell culture medium was measured using a commercial LDH kit, whereas ELISA was conducted to assess the secretory function of IL-1β. Western blot assays were conducted to determine the expression or regulation of proteins associated with apoptosis and pyroptosis. Subcutaneous tumor model of nude mice was established to evaluate the anticancer activity of ATL in vivo. The expression of Ki67, cyclin B1, cleaved-PARP, cleaved-caspase 3, and IL-1β in the animal tumor tissues was profiled using immunohistochemistry analyses.

RESULTS

Our data showed that ATL significantly inhibited the proliferation and colony formation activity of ATC cells. ATL induced ATC cell cycle arrest at G2/M phase, and downregulated the expression of cyclin B1 and CDC2. Furthermore, ATL induced concurrent apoptosis and pyroptosis in the ATC cells, and the cleavage of PARP and GSDME. It also significantly increased the release of LDH and IL-1β. Mechanically, ATL-mediated increase in ROS suppressed the Bcl-2/Bax ratio, downregulated the mitochondrial membrane potential and increased the release of cytochrome c, leading to caspase 9 and caspase 3 cleavage. We also found that ATL induced the translocation of an immunogenic cell death marker (calreticulin) to the cell membrane. In addition, it inhibited the growth of the ATC subcutaneous xenograft model, and activated proteins associated with apoptosis and pyroptosis, with a high safety profile.

CONCLUSION

Taken together, these results firstly demonstrated that ATL exerted an anti-ATC activity by inducing concurrent apoptosis and GSDME-dependent pyroptosis through ROS-mediated mitochondria-dependent caspase activation. Meanwhile, these cell deaths exhibited obvious characteristics of immunogenic cell death, which may synergistically increase the potential of cancer immunotherapy in ATC. Further studies are needed to explore deeper mechanisms for the anti- ATC activity of ATL.

CgCaspase-3 activates the translocation of CgGSDME in haemocytes of Pacific oyster Crassostrea gigas

Cysteinyl aspartate specific proteinase-3 (Caspase-3) is an important protein involved in the apoptosis and gasdermin E (GSDME)-mediated cell pyroptosis pathways in vertebrates. A Caspase-3 homologue (designated as CgCaspase-3) was previously identified as an immune receptor specific for lipopolysaccharide (LPS) to regulate apoptosis in the Pacific oyster Crassostrea gigas. In the present study, the binding activity of CgCaspase-3 to different pathogen associated molecular patterns (PAMPs) and its effects on CgGSDME translocation in haemocytes were further investigated in C. gigas. The mRNA expression of CgCaspase-3 could be detected in all the tested tissues, including hepatopancreas, labial palp, adductor muscle, gonad, gill, mantle and haemocytes, and it was highly expressed in labial palp, gonad, haemocytes, and adductor muscle. The mRNA expression of CgCaspase-3 in haemocytes increased significantly at 3, 24, 48 and 72 h after LPS stimulation, and it increased significantly at 6, 12, 24 and 48 h after Vibrio splendidus stimulation. The recombinant CgCaspase-3 displayed binding activity towards LPS, mannose (MAN), peptidoglycan (PGN), and polyinosinic-polycytidylic acid potassium salt (Poly (I:C)). The positive signals of CgGSDME on haemocyte membrane became stronger at 3 h after V. splendidus stimulation, compared with that of Seawater group, and the co-localization of CgCaspase-3 and CgGSDME was observed in the haemocyte membrane. After the injection of dsCgCaspase-3, the positive signals of CgGSDME on haemocyte membrane became weaker compared with that of EGFP-RNAi group at 24 h after V. splendidus stimulation. The results suggested that CgCaspase-3 was able to bind diverse PAMPs and activate the translocation of CgGSDME in haemocytes of oyster response against pathogen invasion.

Regulation of dietary polyphenols on cancer cell pyroptosis and the tumor immune microenvironment

Cancer is a major public health problem that threatens human life worldwide. In recent years, immunotherapy has made great progress in both clinical and laboratory research. But the high heterogeneity and dynamics of tumors makes immunotherapy not suitable for all cancers. Dietary polyphenols have attracted researchers' attention due to their ability to induce cancer cell pyroptosis and to regulate the tumor immune microenvironment (TIME). This review expounds the regulation of dietary polyphenols and their new forms on cancer cell pyroptosis and the TIME. These dietary polyphenols include curcumin (CUR), resveratrol (RES), epigallocatechin gallate (EGCG), apigenin, triptolide (TPL), kaempferol, genistein and moscatilin. New forms of dietary polyphenols refer to their synthetic analogs and nano-delivery, liposomes. Studies in the past decade are included. The result shows that dietary polyphenols induce pyroptosis in breast cancer cells, liver cancer cells, oral squamous cells, carcinoma cells, and other cancer cells through different pathways. Moreover, dietary polyphenols exhibit great potential in the TIME regulation by modulating the programmed cell death protein 1(PD-1)/programmed death-ligand 1 (PD-L1) axis, enhancing antitumor immune cells, weakening the function and activity of immunosuppressive cells, and targeting tumor-associated macrophages (TAMs) to reduce their tumor infiltration and promote their polarization toward the M1 type. Dietary polyphenols are also used with radiotherapy and chemotherapy to improve antitumor immunity and shape a beneficial TIME. In conclusion, dietary polyphenols induce cancer cell pyroptosis and regulate the TIME, providing new ideas for safer cancer cures.

Efficacy of Digestive Endoscope Based on Artificial Intelligence System in Diagnosing Early Esophageal Carcinoma

Objective

To explore the efficacy of digestive endoscopy (DEN) based on artificial intelligence (AI) system in diagnosing early esophageal carcinoma.

Methods

The clinical data of 300 patients with suspected esophageal carcinoma treated in our hospital from January 2018 to January 2020 were retrospectively analyzed; among them, 198 were diagnosed with esophageal carcinoma after pathological examination, and 102 had benign esophageal lesion. An AI system based on convolutional neural network (CNN) was adopted to assess the DEN images of patients with early esophageal carcinoma. A total of 200 patients (148 with early esophageal carcinoma and 52 with benign esophageal lesion) were selected as the learning group for the Inception V3 image classification system to learn; and the rest 100 patients (50 with early esophageal carcinoma and 50 with benign esophageal lesion) were included in the diagnosis group for the Inception V3 system to assist the narrow-band imaging (NBI) with diagnosis. The diagnosis results from Inception V3-assisted NBI were compared with those from imaging physicians, and the diagnostic efficacy diagram was drawn.

Results

The diagnosis rate of AI-NBI was significantly faster than that of physician diagnosis (0.02 ± 0.01 vs. 5.65 ± 0.32 s (mean rate of two physicians), P < 0.001); between AI-NBI diagnosis and physician diagnosis, no statistical differences in sensitivity (90.0% vs. 92.0%), specificity (92.0% vs. 94.0%), and accuracy (91.0% vs. 93.0%) were observed (P > 0.05); and according to the ROC curves, AUC (95% CI) of AI-NBI diagnosis = 0.910 (0.845-0.975), and AUC (95% CI) of physician diagnosis = 0.930 (0.872-0.988).

Conclusion

CNN-based AI system can assist NBI in screening early esophageal carcinoma, which has a good application prospect in the clinical diagnosis of early esophageal carcinoma.